I was thinking about a way to shut down the inverter when your fridge doesn’t need it and save yourself the sometimes astronomical parasitic loss of the inverter running for no reason. My idea is this:
Use two starter solenoids (like the ones used on old Ford trucks), running parallel between the battery and the inverter. I suppose it could be done on either positive or ground. Then connect a temp sending unit to one of them and connect a signal wire that is tapped into the compressors power wire to the other. That way once the temp gets too high the temp sensor would activate the first solenoid (you could even run two of them in parallel for a dual zone fridge so it would activate the solenoid if either one got too hot) that would give power to the inverter and ideally turn it on and give power to the fridge, which would activate the compressor and give power to the second solenoid and close it. Then as the temp drops the first solenoid would open, but the second would continue supplying power until the compressor shuts off due to the fridge being back down to temp according to the fridges built in temp sensing. The solenoids are designed to withstand a pretty high amount of current for a starter, but I would have to look up what the specs are. I’m not sure it would work on the compressor side though because I believe that gets 120v, definitely not 12... so it would likely need something a bit beefier...
Please let me know what you guys think, and if you have any ideas on where to source a solenoid or similar switch that would work on the high voltage side. My other concern is that a starter solenoid may not like the continuous current considering they’re normally closed for a short period to start the car and then open right back up. Finally, the only way for this to work is if you assume the inverter will allow you to turn it on and off just by disconnecting/reconnecting it when the switch is left on, or would you need to cycle the power switch? Please, all ideas and opinions are greatly appreciated.
thanks
ps. it would be much easier if there was a remote circuit which you could simply control with relays instead. Is that a thing? Or just a dream?
Edit: Turns out many inverters do have a remote circuit, and I figured out a cheap, easy way to take advantage of that to automatically turn on and off your inverter at a temperature of your choosing! See me the post after next and I'll explain it all and include (non-affiliate) links to parts.
Use two starter solenoids (like the ones used on old Ford trucks), running parallel between the battery and the inverter. I suppose it could be done on either positive or ground. Then connect a temp sending unit to one of them and connect a signal wire that is tapped into the compressors power wire to the other. That way once the temp gets too high the temp sensor would activate the first solenoid (you could even run two of them in parallel for a dual zone fridge so it would activate the solenoid if either one got too hot) that would give power to the inverter and ideally turn it on and give power to the fridge, which would activate the compressor and give power to the second solenoid and close it. Then as the temp drops the first solenoid would open, but the second would continue supplying power until the compressor shuts off due to the fridge being back down to temp according to the fridges built in temp sensing. The solenoids are designed to withstand a pretty high amount of current for a starter, but I would have to look up what the specs are. I’m not sure it would work on the compressor side though because I believe that gets 120v, definitely not 12... so it would likely need something a bit beefier...
Please let me know what you guys think, and if you have any ideas on where to source a solenoid or similar switch that would work on the high voltage side. My other concern is that a starter solenoid may not like the continuous current considering they’re normally closed for a short period to start the car and then open right back up. Finally, the only way for this to work is if you assume the inverter will allow you to turn it on and off just by disconnecting/reconnecting it when the switch is left on, or would you need to cycle the power switch? Please, all ideas and opinions are greatly appreciated.
thanks
ps. it would be much easier if there was a remote circuit which you could simply control with relays instead. Is that a thing? Or just a dream?
Edit: Turns out many inverters do have a remote circuit, and I figured out a cheap, easy way to take advantage of that to automatically turn on and off your inverter at a temperature of your choosing! See me the post after next and I'll explain it all and include (non-affiliate) links to parts.
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